diff --git a/src/ccnl-utils/CMakeLists.txt b/src/ccnl-utils/CMakeLists.txt
index 3caa98358..e0f553c6d 100644
--- a/src/ccnl-utils/CMakeLists.txt
+++ b/src/ccnl-utils/CMakeLists.txt
@@ -9,83 +9,81 @@ link_directories(
     ${CMAKE_CURRENT_BINARY_DIR}/../lib
 )
 
-include_directories(
-    ../ccnl-pkt/include
-    ../ccnl-fwd/include
-    ../ccnl-core/include
-    ../ccnl-unix/include
-    ../ccnl-nfn/include
-)
+# set include directories
+include_directories(include ../ccnl-pkt/include ../ccnl-fwd/include ../ccnl-core/include ../ccnl-unix/include ../ccnl-nfn/include)
+
+add_library(common STATIC src/ccnl-common.c src/base64.c src/ccnl-socket.c)
+add_library(ccnl-crypto STATIC src/ccnl-crypto.c src/ccnl-ext-hmac.c src/lib-sha256.c)
 
-add_executable(ccn-lite-peek ccn-lite-peek.c)
+add_executable(ccn-lite-peek src/ccn-lite-peek.c)
 #add_executable(ccn-lite-peekcomputation ccn-lite-peekcomputation.c) #todo work to do
-add_executable(ccn-lite-ctrl ccn-lite-ctrl.c)
-add_executable(ccn-lite-fetch ccn-lite-fetch.c)
+add_executable(ccn-lite-ctrl src/ccn-lite-ctrl.c)
+add_executable(ccn-lite-fetch src/ccn-lite-fetch.c) 
 if(OpenSSL_FOUND)
-    add_executable(ccn-lite-ccnb2xml ccn-lite-ccnb2xml.c)
-    add_executable(ccn-lite-cryptoserver ccn-lite-cryptoserver.c)
+    add_executable(ccn-lite-ccnb2xml src/ccn-lite-ccnb2xml.c)
+    add_executable(ccn-lite-cryptoserver src/ccn-lite-cryptoserver.c)
     #add_executable(ccn-lite-deF ccn-lite-deF.c)
-    add_executable(ccn-lite-mkC ccn-lite-mkC.c)
-    add_executable(ccn-lite-valid ccn-lite-valid.c)
-    add_executable(ccn-lite-rpc ccn-lite-rpc.c)
+    add_executable(ccn-lite-mkC src/ccn-lite-mkC.c)
+    add_executable(ccn-lite-valid src/ccn-lite-valid.c)
+    add_executable(ccn-lite-rpc src/ccn-lite-rpc.c)
 endif()
 
 if(USE_FRAG)
-    add_executable(ccn-lite-mkF ccn-lite-mkF.c)
+    add_executable(ccn-lite-mkF src/ccn-lite-mkF.c)
 endif()
-add_executable(ccn-lite-mkI ccn-lite-mkI.c)
-add_executable(ccn-lite-pktdump ccn-lite-pktdump.c)
-add_executable(ccn-lite-produce ccn-lite-produce.c)
+add_executable(ccn-lite-mkI src/ccn-lite-mkI.c)
+add_executable(ccn-lite-pktdump src/ccn-lite-pktdump.c)
+add_executable(ccn-lite-produce src/ccn-lite-produce.c)
 
-add_executable(ccn-lite-simplenfn ccn-lite-simplenfn.c)
+add_executable(ccn-lite-simplenfn src/ccn-lite-simplenfn.c)
 
 
 target_link_libraries(ccn-lite-peek ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-peek ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-peek ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
 
 #target_link_libraries(ccn-lite-peekcomputation ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})#todo work to do
 #target_link_libraries(ccn-lite-peekcomputation ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
 
 target_link_libraries(ccn-lite-ctrl ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-ctrl ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-ctrl ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn crypto)
 
 if(OpenSSL_FOUND)
     target_link_libraries(ccn-lite-ccnb2xml ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
-    target_link_libraries(ccn-lite-ccnb2xml ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
+    target_link_libraries(ccn-lite-ccnb2xml ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ccnl-crypto ${OPENSSL_LIBRARIES})
 
     target_link_libraries(ccn-lite-cryptoserver ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
-    target_link_libraries(ccn-lite-cryptoserver ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
+    target_link_libraries(ccn-lite-cryptoserver ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ccnl-crypto ${OPENSSL_LIBRARIES} common)
 
     #target_link_libraries(ccn-lite-deF ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
     #target_link_libraries(ccn-lite-deF ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
 
-    target_link_libraries(ccn-lite-mkC ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
-    target_link_libraries(ccn-lite-mkC ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
+    target_link_libraries(ccn-lite-mkC ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES} common)
+    target_link_libraries(ccn-lite-mkC ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ccnl-crypto ${OPENSSL_LIBRARIES})
 
-    target_link_libraries(ccn-lite-valid ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
+    target_link_libraries(ccn-lite-valid ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES} common ccnl-crypto)
     target_link_libraries(ccn-lite-valid ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
 
-    target_link_libraries(ccn-lite-rpc ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES})
+    target_link_libraries(ccn-lite-rpc ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS} ${OPENSSL_LIBRARIES} common)
     target_link_libraries(ccn-lite-rpc ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn ${OPENSSL_LIBRARIES})
 
 endif()
 
 target_link_libraries(ccn-lite-fetch ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-fetch ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-fetch ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
 
 if(USE_FRAG)
     target_link_libraries(ccn-lite-mkF ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-    target_link_libraries(ccn-lite-mkF ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+    target_link_libraries(ccn-lite-mkF ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
 endif()
 
 target_link_libraries(ccn-lite-mkI ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-mkI ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-mkI ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
 
 target_link_libraries(ccn-lite-pktdump ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-pktdump ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-pktdump ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
 
 target_link_libraries(ccn-lite-produce ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-produce ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-produce ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common ccnl-crypto)
 
 target_link_libraries(ccn-lite-simplenfn ${PROJECT_LINK_LIBS} ${EXT_LINK_LIBS})
-target_link_libraries(ccn-lite-simplenfn ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn)
+target_link_libraries(ccn-lite-simplenfn ccnl-core ccnl-pkt ccnl-fwd ccnl-unix ccnl-nfn common)
diff --git a/src/ccnl-utils/include/base64.h b/src/ccnl-utils/include/base64.h
new file mode 100644
index 000000000..3d0e3dbd5
--- /dev/null
+++ b/src/ccnl-utils/include/base64.h
@@ -0,0 +1,55 @@
+// base64.c
+// from stackoverflow.com, user RYYST
+
+#ifndef BASE64_H
+#define BASE64_H
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdint.h>
+
+/**
+ * @brief Initializes the base64 decoding table
+ */
+void base64_build_decoding_table(void);
+
+/**
+ * @brief Encodes a string \p data into a base64 string
+ *
+ * @param[in] data The data to encode
+ * @param[in] input_length The size of the data to encode
+ * @param[out] output_length The size of the encoded date
+ *
+ * @return Upon success, a base64 encoded representation of \p data 
+ * @return NULL if \p data was NULL
+ * @return NULL if allocating the result string failed
+ * @return NULL if \p input_length is not in multiples of four
+ */
+char *base64_encode(const char *data,
+               size_t input_length,
+               size_t *output_length);
+
+/**
+ * @brief Decodes a string \p data into a base64 string
+ *
+ * @param[in] data The data to decode
+ * @param[in] input_length The size of the data to decode
+ * @param[out] output_length The size of the decoded date
+ * 
+ * @return Upon success, the base64 decoded \p data 
+ * @return NULL if \p data was NULL
+ * @return NULL if allocating the result string failed
+ * @return NULL if \p input_length is not in multiples of four
+ */
+unsigned char *base64_decode(const char *data,
+                             size_t input_length,
+                             size_t *output_length);
+
+/**
+ * @brief Frees the previously allocated decoding table
+ */
+void base64_cleanup(void);
+
+#endif // EOF
+/** @} */
diff --git a/src/ccnl-utils/include/ccnl-common.h b/src/ccnl-utils/include/ccnl-common.h
new file mode 100644
index 000000000..ae9e30a92
--- /dev/null
+++ b/src/ccnl-utils/include/ccnl-common.h
@@ -0,0 +1,154 @@
+/**
+ * @addtogroup CCNL-utils
+ * @{
+ *
+ * @file ccnl-common.h
+ * @brief Common functions for the CCN-lite utilities
+ *
+ * Copyright (C) 2013-18 Christian Tschudin, University of Basel
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef CCNL_COMMON_H
+#define CCNL_COMMON_H
+
+#ifndef CCNL_UAPI_H_    // if CCNL_UAPI_H_ is defined then the following config is taken care elsewhere in the code composite
+
+
+#define _DEFAULT_SOURCE
+#define _BSD_SOURCE
+#define _SVID_SOURCE
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <limits.h>
+
+#include <arpa/inet.h>
+#include <sys/types.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/stat.h>
+#include <sys/un.h>
+
+#include "base64.h"
+
+#include "ccnl-os-includes.h"
+#include "ccnl-defs.h"
+#include "ccnl-core.h"
+#include "ccnl-pkt-builder.h"
+#include "ccnl-malloc.h"
+#include "ccnl-os-time.h"
+#include "ccnl-logging.h"
+#include "ccnl-pkt-builder.h"
+
+#ifndef USE_DEBUG_MALLOC
+#define ccnl_malloc(s)                  malloc(s)
+#define ccnl_calloc(n,s)                calloc(n,s)
+#define ccnl_realloc(p,s)               realloc(p,s)
+#define ccnl_free(p)                    free(p)
+#endif //USE_DEBUG_MALLOC
+#define free_2ptr_list(a,b)     ccnl_free(a), ccnl_free(b)
+
+struct ccnl_prefix_s* ccnl_prefix_new(int suite, int cnt);
+int ccnl_pkt_prependComponent(int suite, char *src, int *offset, unsigned char *buf);
+
+#include "ccnl-core.h"
+#include "ccnl-pkt-ccnb.h"
+#include "ccnl-pkt-ccntlv.h"
+#include "ccnl-pkt-localrpc.h"
+#include "ccnl-pkt-ndntlv.h"
+#include "ccnl-pkt-switch.h"
+
+#include "ccnl-socket.h"
+
+#define ccnl_core_addToCleanup(b)       do{}while(0)
+
+// include only the utils, not the core routines:
+#ifdef USE_FRAG
+#include "../ccnl-frag.h"
+#endif
+
+#else // CCNL_UAPI_H_ is defined
+
+#include "base64.c"
+#ifdef RIOT_VERSION
+#include "ccnl-defs.h"
+#include "net/packet.h"
+#include <unistd.h>
+#include "sys/socket.h"
+#include "ccn-lite-riot.h"
+#include "ccnl-headers.h"
+#include "ccnl-pkt-ndntlv.h"
+#include "ccnl-pkt-ccntlv.h"
+#include "ccnl-pkt-ccnb.h"
+
+
+extern int ccnl_suite2defaultPort(int suite);
+#endif
+
+#endif // CCNL_UAPI_H_
+
+
+// ----------------------------------------------------------------------
+
+const char* ccnl_enc2str(int enc);
+
+// ----------------------------------------------------------------------
+
+#define extractStr(VAR,DTAG) \
+    if (typ == CCN_TT_DTAG && num == DTAG) { \
+        char *s; unsigned char *valptr; int vallen; \
+        if (ccnl_ccnb_consume(typ, num, &buf, &buflen, &valptr, &vallen) < 0) \
+                goto Bail; \
+        s = ccnl_malloc(vallen+1); if (!s) goto Bail; \
+        memcpy(s, valptr, vallen); s[vallen] = '\0'; \
+        ccnl_free(VAR); \
+        VAR = (unsigned char*) s; \
+        continue; \
+    } do {} while(0)
+
+#define extractStr2(VAR,DTAG) \
+    if (typ == CCN_TT_DTAG && num == DTAG) { \
+        char *s; unsigned char *valptr; int vallen; \
+        if (ccnl_ccnb_consume(typ, num, buf, buflen, &valptr, &vallen) < 0) \
+                goto Bail; \
+        s = ccnl_malloc(vallen+1); if (!s) goto Bail; \
+        memcpy(s, valptr, vallen); s[vallen] = '\0'; \
+        ccnl_free(VAR); \
+    VAR = (unsigned char*) s; \
+        continue; \
+    } do {} while(0)
+
+// ----------------------------------------------------------------------
+
+struct key_s {
+    struct key_s *next;
+    unsigned char* key;
+    int keylen;
+};
+
+struct key_s* load_keys_from_file(char *path);
+
+// ----------------------------------------------------------------------
+
+int
+ccnl_parseUdp(char *udp, int suite, char **addr, int *port);
+
+#endif 
+/** @} */
diff --git a/src/ccnl-utils/include/ccnl-crypto.h b/src/ccnl-utils/include/ccnl-crypto.h
new file mode 100644
index 000000000..06773fb47
--- /dev/null
+++ b/src/ccnl-utils/include/ccnl-crypto.h
@@ -0,0 +1,47 @@
+/**
+ * @addtogroup CCNL-utils
+ * @{
+ *
+ * @file ccnl-crypto.h
+ * @brief Crypto functions for CCN-lite utilities
+ *
+ * Copyright (C) 2013-2018, Christian Tschudin, University of Basel
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef CCNL_CRYPTO_H
+#define CCNL_CRYPTO_H
+
+#ifdef USE_SIGNATURES
+#include <openssl/pem.h>
+#include <openssl/sha.h>
+#include <openssl/rsa.h>
+#include <openssl/objects.h>
+#include <openssl/err.h>
+#endif
+
+int sha(void* input, unsigned long length, unsigned char* md);
+
+int sign(char* private_key_path, unsigned char *msg, int msg_len,
+     unsigned char *sig, unsigned int *sig_len);
+
+int
+verify(char* public_key_path, unsigned char *msg, int msg_len,
+       unsigned char *sig, unsigned int sig_len);
+
+int
+add_signature(unsigned char *out, char *private_key_path,
+              unsigned char *file, unsigned int fsize);
+
+#endif 
+/** @} */
diff --git a/src/ccnl-utils/include/ccnl-ext-hmac.h b/src/ccnl-utils/include/ccnl-ext-hmac.h
new file mode 100644
index 000000000..f63c771d7
--- /dev/null
+++ b/src/ccnl-utils/include/ccnl-ext-hmac.h
@@ -0,0 +1,145 @@
+/**
+ * @addtogroup CCNL-utils
+ * @{
+ *
+ * @file ccnl-ext-hmac.h
+ * @brief HMAC-256 signing support based on RFC 2104
+ *
+ * Copyright (C) 2015-18 <christian.tschudin@unibas.ch>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef CCNL_EXT_MAC_H_
+#define CCNL_EXT_MAC_H_
+
+#include "lib-sha256.h"
+
+#include "ccnl-pkt-ccnb.h"
+#include "ccnl-pkt-ccntlv.h"
+#include "ccnl-pkt-localrpc.h"
+#include "ccnl-pkt-ndntlv.h"
+#include "ccnl-pkt-switch.h"
+
+/**
+ * @brief Generates an HMAC key
+ * 
+ * @note The \p keyval must be of at least 64 bytes (block length). 
+ *
+ * The function either copies \p klen bytes of \p key or generates a new
+ * key.
+ *
+ * @param[in] key The value of the key (to be copied or generated)
+ * @param[in] klen The length of the key
+ * @param[in] keyval The (final) key (to be copied or generated)
+ */
+void ccnl_hmac256_keyval(unsigned char *key, int klen, unsigned char *keyval); 
+
+/**
+ * @brief TODO
+ * 
+ * @note The \p keyid must be of at least 32 bytes (digest length). 
+ *
+ * @param[in] key The actual key
+ * @param[in] klen The length of the key
+ * @param[in] keyid TODO
+ */
+void
+ccnl_hmac256_keyid(unsigned char *key, int klen,
+                   unsigned char *keyid); 
+
+/**
+ * @brief Adds padding bytes to a key 
+ * 
+ * @param[in] ctx Context 'object' of the underlying SHA256 implementation
+ * @param[in] keyval The key to pad
+ * @param[in] kvlen The length of the key
+ * @param[in] pad The padding byte
+ */
+void
+ccnl_hmac256_keysetup(SHA256_CTX_t *ctx, unsigned char *keyval, int kvlen,
+                      unsigned char pad);
+
+/**
+ * @brief Generates an HMAC signature
+ * 
+ * @param[in]  keyval The key
+ * @param[in]  kvlen The lengthof the key
+ * @param[in]  data The data to sign
+ * @param[in]  dlen The length of the sign
+ * @param[in]  md The message digest
+ * @param[out] mlen The length of the message digest
+ */
+void
+ccnl_hmac256_sign(unsigned char *keyval, int kvlen,
+                  unsigned char *data, int dlen,
+                  unsigned char *md, int *mlen);
+
+
+#ifdef NEEDS_PACKET_CRAFTING
+#ifdef USE_SUITE_CCNTLV
+/**
+ * @brief Signs CCNx content and prepends signature with the header
+ *
+ * @note The content is before the \p offset in \p buf. The function adjusts the
+ * \p offset.
+ *
+ * @param[in]  name The prefix of the content to sign
+ * @param[in]  payload The actual content
+ * @param[in]  paylen The length of \p payload
+ * @param[in]  lastchunknum Position of the last chunk in the \p buf
+ * @param[in]  contentpos Position of the content in the \p buf
+ * @param[in]  keyval The key to use for signing the content (>= 64 bytes)
+ * @param[in]  keydigest The digest (>= 32 bytes)
+ * @param[out] offset TODO
+ * @param[out] buf A byte representation of the actual packet
+ *
+ * @return Upon success, the function returns the number of used bytes
+ */
+int
+ccnl_ccntlv_prependSignedContentWithHdr(struct ccnl_prefix_s *name,
+                                        unsigned char *payload, int paylen,
+                                        unsigned int *lastchunknum,
+                                        int *contentpos,
+                                        unsigned char *keyval, 
+                                        unsigned char *keydigest, 
+                                        int *offset, unsigned char *buf);
+#endif // USE_SUITE_CCNTLV
+
+#ifdef USE_SUITE_NDNTLV
+/**
+ * @brief Signs an NDO and prepends signature
+ *
+ * @param[in]  name The prefix of the content to sign
+ * @param[in]  payload The actual content
+ * @param[in]  paylen The length of \p payload
+ * @param[in]  final_block_id Denotes position of optional MetaInfo fields
+ * @param[in]  contentpos Position of the content in the \p buf
+ * @param[in]  keyval The key to use for signing the content (>= 64 bytes)
+ * @param[in]  keydigest The digest (>= 32 bytes)
+ * @param[out] offset TODO
+ * @param[out] buf A byte representation of the actual packet
+ * 
+ * @return Upon success, the function returns the number of used bytes
+ */
+int
+ccnl_ndntlv_prependSignedContent(struct ccnl_prefix_s *name,
+                           unsigned char *payload, int paylen,
+                           unsigned int *final_block_id, int *contentpos,
+                           unsigned char *keyval, 
+                           unsigned char *keydigest, 
+                           int *offset, unsigned char *buf);
+#endif // USE_SUITE_NDNTLV
+#endif // NEEDS_PACKET_CRAFTING
+
+#endif 
+/** @} */
diff --git a/src/ccnl-utils/include/ccnl-socket.h b/src/ccnl-utils/include/ccnl-socket.h
new file mode 100644
index 000000000..28293d641
--- /dev/null
+++ b/src/ccnl-utils/include/ccnl-socket.h
@@ -0,0 +1,57 @@
+/**
+ * @addtogroup CCNL-utils
+ * @{
+ *
+ * @file ccnl-socket.h
+ * @brief Request content: send an interest open socket etc
+ *
+ * Copyright (C) 2013-18, Christian Tschudin, University of Basel
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef CCNL_SOCKET_H
+#define CCNL_SOCKET_H
+
+#include <ctype.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+void myexit(int rc);
+
+int udp_open(void);
+
+int udp_sendto(int sock, char *dest, unsigned char *data, int len);
+
+
+int ux_open(void);
+
+int ux_sendto(int sock, char *topath, unsigned char *data, int len);
+
+int block_on_read(int sock, float wait);
+
+void request_content(int sock, int (*sendproc)(int,char*,unsigned char*,int),
+                char *dest, unsigned char *out, int len, float wait);
+
+#endif 
+/** @} */
diff --git a/src/ccnl-utils/include/lib-sha256.h b/src/ccnl-utils/include/lib-sha256.h
new file mode 100644
index 000000000..964fd8c23
--- /dev/null
+++ b/src/ccnl-utils/include/lib-sha256.h
@@ -0,0 +1,128 @@
+/*
+ * @f lib-sha256.c
+ * @b implementation of NIST SHA256, based on Aaron Gifford's code
+ *
+ */
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+
+#ifdef CCNL_ARDUINO
+# define _MEMLOCATION_ PROGMEM
+# define K256_(i)      pgm_read_dword_near(K256 + i)
+#else
+# define _MEMLOCATION_
+# define K256_(i) K256[i]
+#endif
+
+/*
+ * AUTHOR:	Aaron D. Gifford - http://www.aarongifford.com/
+ *
+ * Copyright (c) 2000-2001, Aaron D. Gifford
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the copyright holder nor the names of contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTOR(S) ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTOR(S) BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id: sha2.h,v 1.1 2001/11/08 00:02:01 adg Exp adg $
+ */
+
+// basic definitions
+
+#define SHA256_BLOCK_LENGTH		64
+#define SHA256_DIGEST_LENGTH		32
+#define SHA256_DIGEST_STRING_LENGTH	(SHA256_DIGEST_LENGTH * 2 + 1)
+#define SHA256_SHORT_BLOCK_LENGTH	(SHA256_BLOCK_LENGTH - 8)
+
+typedef struct _SHA256_CTX {
+	uint32_t	state[8];
+	uint64_t	bitcount;
+	uint8_t	buffer[SHA256_BLOCK_LENGTH];
+} SHA256_CTX_t;
+
+typedef uint8_t  sha2_byte;	/* Exactly 1 byte */
+typedef uint32_t sha2_word32;	/* Exactly 4 bytes */
+typedef uint64_t sha2_word64;	/* Exactly 8 bytes */
+
+
+// reversal macros
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define REVERSE32(w,x)	{ \
+	sha2_word32 tmp = (w); \
+	tmp = (tmp >> 16) | (tmp << 16); \
+	(x) = ((tmp & 0xff00ff00UL) >> 8) | ((tmp & 0x00ff00ffUL) << 8); \
+}
+#define REVERSE64(w,x)	{ \
+	sha2_word64 tmp = (w); \
+	tmp = (tmp >> 32) | (tmp << 32); \
+	tmp = ((tmp & 0xff00ff00ff00ff00ULL) >> 8) | \
+	      ((tmp & 0x00ff00ff00ff00ffULL) << 8); \
+	(x) = ((tmp & 0xffff0000ffff0000ULL) >> 16) | \
+	      ((tmp & 0x0000ffff0000ffffULL) << 16); \
+}
+#endif /* BYTE_ORDER == LITTLE_ENDIAN */
+
+#define MEMSET_BZERO(p,l)	memset((p), 0, (l))
+#define MEMCPY_BCOPY(d,s,l)	memcpy((d), (s), (l))
+
+/*** THE SIX LOGICAL FUNCTIONS ****************************************/
+/*
+ * Bit shifting and rotation (used by the six SHA-XYZ logical functions:
+ *
+ *   NOTE:  The naming of R and S appears backwards here (R is a SHIFT and
+ *   S is a ROTATION) because the SHA-256/384/512 description document
+ *   (see http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf) uses this
+ *   same "backwards" definition.
+ */
+/* Shift-right (used in SHA-256, SHA-384, and SHA-512): */
+#define R(b,x) 		((x) >> (b))
+/* 32-bit Rotate-right (used in SHA-256): */
+#define S32(b,x)	(((x) >> (b)) | ((x) << (32 - (b))))
+/* 64-bit Rotate-right (used in SHA-384 and SHA-512): */
+#define S64(b,x)	(((x) >> (b)) | ((x) << (64 - (b))))
+
+/* Two of six logical functions used in SHA-256, SHA-384, and SHA-512: */
+#define Ch(x,y,z)	(((x) & (y)) ^ ((~(x)) & (z)))
+#define Maj(x,y,z)	(((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
+
+/* Four of six logical functions used in SHA-256: */
+#define Sigma0_256(x)	(S32(2,  (x)) ^ S32(13, (x)) ^ S32(22, (x)))
+#define Sigma1_256(x)	(S32(6,  (x)) ^ S32(11, (x)) ^ S32(25, (x)))
+#define sigma0_256(x)	(S32(7,  (x)) ^ S32(18, (x)) ^ R(3 ,   (x)))
+#define sigma1_256(x)	(S32(17, (x)) ^ S32(19, (x)) ^ R(10,   (x)))
+
+
+/*** SHA-256: *********************************************************/
+
+void ccnl_SHA256_Init(SHA256_CTX_t* context);
+
+void ccnl_SHA256_Transform(SHA256_CTX_t* context, const sha2_word32* data);
+
+
+void ccnl_SHA256_Update(SHA256_CTX_t* context, const sha2_byte *data, size_t len);
+
+void ccnl_SHA256_Final(sha2_byte digest[], SHA256_CTX_t* context);
+
+// eof
diff --git a/src/ccnl-utils/base64.c b/src/ccnl-utils/src/base64.c
similarity index 92%
rename from src/ccnl-utils/base64.c
rename to src/ccnl-utils/src/base64.c
index f8c1fd04b..c59e9816d 100644
--- a/src/ccnl-utils/base64.c
+++ b/src/ccnl-utils/src/base64.c
@@ -1,10 +1,8 @@
 // base64.c
 // from stackoverflow.com, user RYYST
 
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdint.h>
+
+#include "base64.h"
 
 static char
 encoding_table[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
@@ -37,8 +35,13 @@ char
     *output_length = 4 * ((input_length + 2) / 3) + 1;
 
     char *encoded_data = (char *) malloc(*output_length);
-    memset(encoded_data, '\0', *output_length);
-    if (encoded_data == NULL) return NULL;
+
+    if (encoded_data == NULL) {
+        return NULL;
+    } else { 
+        memset(encoded_data, '\0', *output_length);
+    }
+
     int i, j;
     for (i = 0, j = 0; (unsigned int) i < input_length;) {
 
@@ -99,7 +102,9 @@ unsigned char
 
 void
 base64_cleanup(void) {
-    free(decoding_table);
+    /** only free the table if it has been allocated before */
+    if (decoding_table != NULL) { 
+        free(decoding_table);
+    }
 }
 
-// eof
diff --git a/src/ccnl-utils/ccn-lite-ccnb2xml.c b/src/ccnl-utils/src/ccn-lite-ccnb2xml.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-ccnb2xml.c
rename to src/ccnl-utils/src/ccn-lite-ccnb2xml.c
index 74cd2e0ee..e695e73d3 100644
--- a/src/ccnl-utils/ccn-lite-ccnb2xml.c
+++ b/src/ccnl-utils/src/ccn-lite-ccnb2xml.c
@@ -20,8 +20,8 @@
  * 2012-07-01  created
  */
 
-#include "ccnl-common.c"
-#include "ccnl-crypto.c"
+#include "ccnl-common.h"
+#include "ccnl-crypto.h"
 
 // ----------------------------------------------------------------------
 
diff --git a/src/ccnl-utils/ccn-lite-cryptoserver.c b/src/ccnl-utils/src/ccn-lite-cryptoserver.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-cryptoserver.c
rename to src/ccnl-utils/src/ccn-lite-cryptoserver.c
index 5de7383e5..bfeed6a86 100644
--- a/src/ccnl-utils/ccn-lite-cryptoserver.c
+++ b/src/ccnl-utils/src/ccn-lite-cryptoserver.c
@@ -21,8 +21,8 @@
  */
 
 
-#include "ccnl-common.c"
-#include "ccnl-crypto.c"
+#include "ccnl-common.h"
+#include "ccnl-crypto.h"
 
 // ----------------------------------------------------------------------
 
diff --git a/src/ccnl-utils/ccn-lite-ctrl.c b/src/ccnl-utils/src/ccn-lite-ctrl.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-ctrl.c
rename to src/ccnl-utils/src/ccn-lite-ctrl.c
index 4f26da16d..9ffb9b2ee 100644
--- a/src/ccnl-utils/ccn-lite-ctrl.c
+++ b/src/ccnl-utils/src/ccn-lite-ctrl.c
@@ -22,8 +22,8 @@
  *             of return message
  */
 
-#include "ccnl-common.c"
-#include "ccnl-crypto.c"
+#include "ccnl-common.h"
+#include "ccnl-crypto.h"
 
 // ----------------------------------------------------------------------
 
diff --git a/src/ccnl-utils/ccn-lite-deF.c b/src/ccnl-utils/src/ccn-lite-deF.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-deF.c
rename to src/ccnl-utils/src/ccn-lite-deF.c
index 8d01718c9..6e89ff657 100644
--- a/src/ccnl-utils/ccn-lite-deF.c
+++ b/src/ccnl-utils/src/ccn-lite-deF.c
@@ -20,7 +20,7 @@
  * 2013-07-06  created
  */
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 #include "ccnl-frag.h"
 
 // ----------------------------------------------------------------------
diff --git a/src/ccnl-utils/ccn-lite-fetch.c b/src/ccnl-utils/src/ccn-lite-fetch.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-fetch.c
rename to src/ccnl-utils/src/ccn-lite-fetch.c
index 45cce884a..5d22a17c7 100644
--- a/src/ccnl-utils/ccn-lite-fetch.c
+++ b/src/ccnl-utils/src/ccn-lite-fetch.c
@@ -23,7 +23,10 @@
 
 //#define NEEDS_PACKET_CRAFTING
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
+
+#include <stdlib.h>
+
 //#include "ccnl-socket.c"
 
 // ----------------------------------------------------------------------
diff --git a/src/ccnl-utils/ccn-lite-mkC.c b/src/ccnl-utils/src/ccn-lite-mkC.c
similarity index 98%
rename from src/ccnl-utils/ccn-lite-mkC.c
rename to src/ccnl-utils/src/ccn-lite-mkC.c
index 3fbedd1a2..86775998b 100644
--- a/src/ccnl-utils/ccn-lite-mkC.c
+++ b/src/ccnl-utils/src/ccn-lite-mkC.c
@@ -23,10 +23,10 @@
 
 //#define NEEDS_PACKET_CRAFTING
 
-#include "ccnl-common.c"
-#include "ccnl-crypto.c"
+#include "ccnl-common.h"
+#include "ccnl-crypto.h"
 #include "ccnl-pkt-ndntlv.h"
-#include "ccnl-ext-hmac.c"
+#include "ccnl-ext-hmac.h"
 
 
 // ----------------------------------------------------------------------
diff --git a/src/ccnl-utils/ccn-lite-mkF.c b/src/ccnl-utils/src/ccn-lite-mkF.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-mkF.c
rename to src/ccnl-utils/src/ccn-lite-mkF.c
index f6a97c8ec..30bb7fa84 100644
--- a/src/ccnl-utils/ccn-lite-mkF.c
+++ b/src/ccnl-utils/src/ccn-lite-mkF.c
@@ -21,7 +21,7 @@
  */
 
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 
 // ----------------------------------------------------------------------
 void
diff --git a/src/ccnl-utils/ccn-lite-mkI.c b/src/ccnl-utils/src/ccn-lite-mkI.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-mkI.c
rename to src/ccnl-utils/src/ccn-lite-mkI.c
index c54ecb63d..36cf32542 100644
--- a/src/ccnl-utils/ccn-lite-mkI.c
+++ b/src/ccnl-utils/src/ccn-lite-mkI.c
@@ -20,7 +20,7 @@
  * 2013-07-06  created
  */
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 
 // ----------------------------------------------------------------------
 
diff --git a/src/ccnl-utils/ccn-lite-ndnstream.py b/src/ccnl-utils/src/ccn-lite-ndnstream.py
similarity index 100%
rename from src/ccnl-utils/ccn-lite-ndnstream.py
rename to src/ccnl-utils/src/ccn-lite-ndnstream.py
diff --git a/src/ccnl-utils/ccn-lite-peek.c b/src/ccnl-utils/src/ccn-lite-peek.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-peek.c
rename to src/ccnl-utils/src/ccn-lite-peek.c
index fa913c472..a919a2e60 100644
--- a/src/ccnl-utils/ccn-lite-peek.c
+++ b/src/ccnl-utils/src/ccn-lite-peek.c
@@ -21,7 +21,7 @@
  * 2014-06-18  added NDNTLV support
  */
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 #include <unistd.h>
 #ifndef assert
 #define assert(...) do {} while(0)
diff --git a/src/ccnl-utils/ccn-lite-peekcomputation.c b/src/ccnl-utils/src/ccn-lite-peekcomputation.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-peekcomputation.c
rename to src/ccnl-utils/src/ccn-lite-peekcomputation.c
index 6bdb893a2..9febccddf 100644
--- a/src/ccnl-utils/ccn-lite-peekcomputation.c
+++ b/src/ccnl-utils/src/ccn-lite-peekcomputation.c
@@ -1,5 +1,5 @@
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 
 
 int
diff --git a/src/ccnl-utils/ccn-lite-pktdump.c b/src/ccnl-utils/src/ccn-lite-pktdump.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-pktdump.c
rename to src/ccnl-utils/src/ccn-lite-pktdump.c
index 4d0ec5a62..8e460cd57 100644
--- a/src/ccnl-utils/ccn-lite-pktdump.c
+++ b/src/ccnl-utils/src/ccn-lite-pktdump.c
@@ -22,9 +22,8 @@
  *
  */
 
-
-
-#include "ccnl-common.c"
+#include "base64.h"
+#include "ccnl-common.h"
 
 // ----------------------------------------------------------------------
 
diff --git a/src/ccnl-utils/ccn-lite-produce.c b/src/ccnl-utils/src/ccn-lite-produce.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-produce.c
rename to src/ccnl-utils/src/ccn-lite-produce.c
index f39f52f81..0dcfec665 100644
--- a/src/ccnl-utils/ccn-lite-produce.c
+++ b/src/ccnl-utils/src/ccn-lite-produce.c
@@ -23,8 +23,8 @@
 
 #define CCNL_MAX_CHUNK_SIZE 4048
 
-#include "ccnl-common.c"
-#include "ccnl-crypto.c"
+#include "ccnl-common.h"
+#include "ccnl-crypto.h"
 
 int
 main(int argc, char *argv[])
diff --git a/src/ccnl-utils/ccn-lite-rpc.c b/src/ccnl-utils/src/ccn-lite-rpc.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-rpc.c
rename to src/ccnl-utils/src/ccn-lite-rpc.c
index f36685ca9..31cd4114b 100644
--- a/src/ccnl-utils/ccn-lite-rpc.c
+++ b/src/ccnl-utils/src/ccn-lite-rpc.c
@@ -20,7 +20,7 @@
  * 2014-05-11  created
  */
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 
 /*
   use examples:
diff --git a/src/ccnl-utils/ccn-lite-simplenfn.c b/src/ccnl-utils/src/ccn-lite-simplenfn.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-simplenfn.c
rename to src/ccnl-utils/src/ccn-lite-simplenfn.c
index 29667a8e7..82f8dbd0d 100644
--- a/src/ccnl-utils/ccn-lite-simplenfn.c
+++ b/src/ccnl-utils/src/ccn-lite-simplenfn.c
@@ -21,7 +21,7 @@
  */
 
 
-#include "ccnl-common.c"
+#include "ccnl-common.h"
 #include "ccnl-nfn-parse.h"
 
 int
diff --git a/src/ccnl-utils/ccn-lite-valid.c b/src/ccnl-utils/src/ccn-lite-valid.c
similarity index 99%
rename from src/ccnl-utils/ccn-lite-valid.c
rename to src/ccnl-utils/src/ccn-lite-valid.c
index b110f6d74..6bcd5ba71 100644
--- a/src/ccnl-utils/ccn-lite-valid.c
+++ b/src/ccnl-utils/src/ccn-lite-valid.c
@@ -21,8 +21,8 @@
  */
 
 #define assert(...) do {} while(0)
-#include "ccnl-common.c"
-#include "ccnl-ext-hmac.c"
+#include "ccnl-common.h"
+#include "ccnl-ext-hmac.h"
 
 struct ccnl_pkt_s*
 ccnl_parse(unsigned char *data, int datalen)
diff --git a/src/ccnl-utils/ccnl-common.c b/src/ccnl-utils/src/ccnl-common.c
similarity index 99%
rename from src/ccnl-utils/ccnl-common.c
rename to src/ccnl-utils/src/ccnl-common.c
index 8986e70bf..34d6f9c49 100644
--- a/src/ccnl-utils/ccnl-common.c
+++ b/src/ccnl-utils/src/ccnl-common.c
@@ -55,7 +55,8 @@
 #include <sys/stat.h>
 #include <sys/un.h>
 
-#include "base64.c"
+#include "base64.h"
+//#include "base64.c"
 
 #include "ccnl-os-includes.h"
 #include "ccnl-defs.h"
diff --git a/src/ccnl-utils/ccnl-crypto.c b/src/ccnl-utils/src/ccnl-crypto.c
similarity index 99%
rename from src/ccnl-utils/ccnl-crypto.c
rename to src/ccnl-utils/src/ccnl-crypto.c
index 9025cbac4..10d257456 100644
--- a/src/ccnl-utils/ccnl-crypto.c
+++ b/src/ccnl-utils/src/ccnl-crypto.c
@@ -22,6 +22,7 @@
 
 // ----------------------------------------------------------------------
 
+#include "ccnl-crypto.h"
 
 #ifdef USE_SIGNATURES
 // ----------------------------------------------------------------------
diff --git a/src/ccnl-utils/ccnl-ext-hmac.c b/src/ccnl-utils/src/ccnl-ext-hmac.c
similarity index 86%
rename from src/ccnl-utils/ccnl-ext-hmac.c
rename to src/ccnl-utils/src/ccnl-ext-hmac.c
index 5e35700ad..38ffbb8ae 100644
--- a/src/ccnl-utils/ccnl-ext-hmac.c
+++ b/src/ccnl-utils/src/ccnl-ext-hmac.c
@@ -1,38 +1,8 @@
-/*
- * @f ccnl-ext-hmac.c
- * @b HMAC-256 signing support
- *
- * Copyright (C) 2015 <christian.tschudin@unibas.ch>
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- *
- * File history:
- * 2015-05-08 created
- */
-
-
-#include "ccnl-pkt-ccnb.h"
-#include "ccnl-pkt-ccntlv.h"
-#include "ccnl-pkt-localrpc.h"
-#include "ccnl-pkt-ndntlv.h"
-#include "ccnl-pkt-switch.h"
-#include "lib-sha256.c"
+#include "ccnl-ext-hmac.h"
 
 #ifdef USE_HMAC256
 
-
-
-// RFC2014 keyval generation
+// RFC2104 keyval generation
 void
 ccnl_hmac256_keyval(unsigned char *key, int klen,
                     unsigned char *keyval) // MUST have 64 bytes (BLOCK_LENGTH)
@@ -92,7 +62,7 @@ ccnl_hmac256_keysetup(SHA256_CTX_t *ctx, unsigned char *keyval, int kvlen,
     ccnl_SHA256_Update(ctx, buf, sizeof(buf));
 }
 
-// RFC2014 signature generation
+// RFC2104 signature generation
 void
 ccnl_hmac256_sign(unsigned char *keyval, int kvlen,
                   unsigned char *data, int dlen,
diff --git a/src/ccnl-utils/ccnl-socket.c b/src/ccnl-utils/src/ccnl-socket.c
similarity index 98%
rename from src/ccnl-utils/ccnl-socket.c
rename to src/ccnl-utils/src/ccnl-socket.c
index e2bb2896b..750fb5ea9 100644
--- a/src/ccnl-utils/ccnl-socket.c
+++ b/src/ccnl-utils/src/ccnl-socket.c
@@ -36,6 +36,9 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
+#include "ccnl-defs.h"
+#include "ccnl-socket.h"
+
 char *unix_path;
 
 void
diff --git a/src/ccnl-utils/lib-sha256.c b/src/ccnl-utils/src/lib-sha256.c
similarity index 77%
rename from src/ccnl-utils/lib-sha256.c
rename to src/ccnl-utils/src/lib-sha256.c
index 2e76f7846..be92525b4 100644
--- a/src/ccnl-utils/lib-sha256.c
+++ b/src/ccnl-utils/src/lib-sha256.c
@@ -3,14 +3,7 @@
  * @b implementation of NIST SHA256, based on Aaron Gifford's code
  *
  */
-
-#ifdef CCNL_ARDUINO
-# define _MEMLOCATION_ PROGMEM
-# define K256_(i)      pgm_read_dword_near(K256 + i)
-#else
-# define _MEMLOCATION_
-# define K256_(i) K256[i]
-#endif
+#include "lib-sha256.h"
 
 /*
  * AUTHOR:	Aaron D. Gifford - http://www.aarongifford.com/
@@ -47,70 +40,6 @@
 
 // basic definitions
 
-#define SHA256_BLOCK_LENGTH		64
-#define SHA256_DIGEST_LENGTH		32
-#define SHA256_DIGEST_STRING_LENGTH	(SHA256_DIGEST_LENGTH * 2 + 1)
-#define SHA256_SHORT_BLOCK_LENGTH	(SHA256_BLOCK_LENGTH - 8)
-
-typedef struct _SHA256_CTX {
-	uint32_t	state[8];
-	uint64_t	bitcount;
-	uint8_t	buffer[SHA256_BLOCK_LENGTH];
-} SHA256_CTX_t;
-
-typedef uint8_t  sha2_byte;	/* Exactly 1 byte */
-typedef uint32_t sha2_word32;	/* Exactly 4 bytes */
-typedef uint64_t sha2_word64;	/* Exactly 8 bytes */
-
-
-// reversal macros
-
-#if BYTE_ORDER == LITTLE_ENDIAN
-#define REVERSE32(w,x)	{ \
-	sha2_word32 tmp = (w); \
-	tmp = (tmp >> 16) | (tmp << 16); \
-	(x) = ((tmp & 0xff00ff00UL) >> 8) | ((tmp & 0x00ff00ffUL) << 8); \
-}
-#define REVERSE64(w,x)	{ \
-	sha2_word64 tmp = (w); \
-	tmp = (tmp >> 32) | (tmp << 32); \
-	tmp = ((tmp & 0xff00ff00ff00ff00ULL) >> 8) | \
-	      ((tmp & 0x00ff00ff00ff00ffULL) << 8); \
-	(x) = ((tmp & 0xffff0000ffff0000ULL) >> 16) | \
-	      ((tmp & 0x0000ffff0000ffffULL) << 16); \
-}
-#endif /* BYTE_ORDER == LITTLE_ENDIAN */
-
-#define MEMSET_BZERO(p,l)	memset((p), 0, (l))
-#define MEMCPY_BCOPY(d,s,l)	memcpy((d), (s), (l))
-
-/*** THE SIX LOGICAL FUNCTIONS ****************************************/
-/*
- * Bit shifting and rotation (used by the six SHA-XYZ logical functions:
- *
- *   NOTE:  The naming of R and S appears backwards here (R is a SHIFT and
- *   S is a ROTATION) because the SHA-256/384/512 description document
- *   (see http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf) uses this
- *   same "backwards" definition.
- */
-/* Shift-right (used in SHA-256, SHA-384, and SHA-512): */
-#define R(b,x) 		((x) >> (b))
-/* 32-bit Rotate-right (used in SHA-256): */
-#define S32(b,x)	(((x) >> (b)) | ((x) << (32 - (b))))
-/* 64-bit Rotate-right (used in SHA-384 and SHA-512): */
-#define S64(b,x)	(((x) >> (b)) | ((x) << (64 - (b))))
-
-/* Two of six logical functions used in SHA-256, SHA-384, and SHA-512: */
-#define Ch(x,y,z)	(((x) & (y)) ^ ((~(x)) & (z)))
-#define Maj(x,y,z)	(((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
-
-/* Four of six logical functions used in SHA-256: */
-#define Sigma0_256(x)	(S32(2,  (x)) ^ S32(13, (x)) ^ S32(22, (x)))
-#define Sigma1_256(x)	(S32(6,  (x)) ^ S32(11, (x)) ^ S32(25, (x)))
-#define sigma0_256(x)	(S32(7,  (x)) ^ S32(18, (x)) ^ R(3 ,   (x)))
-#define sigma1_256(x)	(S32(17, (x)) ^ S32(19, (x)) ^ R(10,   (x)))
-
-
 /*** SHA-XYZ INITIAL HASH VALUES AND CONSTANTS ************************/
 /* Hash constant words K for SHA-256: */
 const sha2_word32 K256[64] _MEMLOCATION_ = {